WO2022072666A1

WO2022072666A1 - Design and manufacture of 3d printed nasopharyngeal swabs

Info

Publication number: WO2022072666A1
Application number: PCT/US2021/052924
Authority: WO
Inventors: Walter Everett VOIT; Hongzhao JI; Caleb James LUND; Pedro Emanuel ROCHA FLORES; Ankit Rajen PARIKH; Benjamin Robert LUND
Original assignee: The University Of Texas At Dallas; Adaptive 3D Technologies; Ut Southwestern Medical Center
Priority date: 2020-09-30
Filing date: 2021-09-30
Publication date: 2022-04-07

Abstract

The present disclosure relates to additive manufacturing, nasopharyngeal swabs, and additive manufacturing of nasopharyngeal swabs, comprising an engraving that denotes a depth of insertion of the nasopharyngeal swab, a geometric head design wherein a head of the geometric head design is hollow, a twist lock adjoining a head to a stem and a fracture point that enables a head to be separated from a stem through mechanical action without use of a cutting tool.

Description

DESIGN AND MANUFACTURE OF 3D PRINTED NASOPHARYNGEAL SWABS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Application No. 63/085,650 filed September 30, 2020, the content of which is incorporated herein by reference in its entirety.

FIELD OF INVENTION

[0002] The present disclosure relates to additive manufacturing, nasopharyngeal swabs, and additive manufacturing of nasopharyngeal swabs.

BACKGROUND

[0003] Additive manufacturing is a process whereby parts are manufactured through the sequential patterning of materials in a layer by layer fashion. Additive manufacturing can be used to pattern polymeric materials which are plastic or elastomeric in nature. There are four main kinds of additive manufacturing for polymers. These include deposition methods, such as Fused Filament Fabrication (FFF) and polymer jetting, as well as light patterning methods, such as laser sintering and stereolithography.

[0004] Additive manufacturing can be used to form a number of objects with internal complexity and can also be used for agile, just-in-time manufacturing. Additive manufacturing is not limited by the conventional constraints of molded manufacturing, such as injection molding, blow molding, etc., however, it may be limited by the processing steps comprising the 3D printing process. In top-down digital light processing (DLP) based additive manufacturing, these steps include, for example, setting up and supporting CAD files, printing by selectively curing the resin with patterned light, removal of the part from the build pate, cleaning of residual resin from the part, removal of the part from the support structures, and post curing of the printed parts. Innovations in these steps are needed to enable the full potential of additive manufacturing up to and including full automation of the 3D printing process.

[0005] Additionally, various diseases, such as the COVID-19 pandemic, can cause significant pain in global marketplaces and may place significant constraints upon the global populace (especially in terms of public gatherings and interactions). The ability to effectively test for, e.g., COVID may help the detection and isolation of carriers. Testing protocols may involve inserting a swab deep into the nasal cavity or the nasopharyngeal cavity and collecting mucosal samples from the nose or back of the nasopharynx. Such processes whereby the sample is collected are often painful, and while subjects may be willing to be tested one time, repeat testing, which may be necessary, may prove challenging if the testing protocols are significantly uncomfortable. Additionally, testing minors may prove challenging as a painful or uncomfortable process may have significant deleterious effects on the willingness of the subjects to undergo the procedure.

[0006] The development of testing methodologies and swabs that significantly decrease patient discomfort and improve patient outcomes is of significant societal and commercial value.

SUMMARY

[0007] In some embodiments, an article comprises a nasopharyngeal swab, and the article comprises an engraving that denotes a depth of insertion of the nasopharyngeal swab.

[0008] In some embodiments, the engraving is a number. In some embodiments, the engraving is a letter. In some embodiments, the engraving is a symbol. In some embodiments, the engraving is a combination of one or more letters, numbers and/or symbols.

[0009] In some embodiments, the edges of the engraving range from > 90 degrees and < 180 degrees. In some embodiments, the edges of the engraving range from > 90 degrees and < 150 degrees. In some embodiments, the edges of the engraving range from > 90 degrees and < 135 degrees. In some embodiments, the edges of the engraving range from > 90 degrees and < 120 degrees.

[0010] In some embodiments, an article comprises a nasopharyngeal swab, and the article comprises a geometric head design wherein a head of the geometric head design is hollow.

[0011] In some embodiments, individual strut thicknesses of the geometric head design range from 0.1 to 1 mm. In some embodiments, individual strut thicknesses of the geometric head design range from 0.2 to 0.8 mm. In some embodiments, individual strut thicknesses of the geometric head design range from 0.4 to 0.6 mm. In some embodiments, individual strut thicknesses of the geometric head design range from 0.45 to 0.55 mm.

[0012] In some embodiments, pores within the head range in diameter. In some embodiments, pores within the head contract in diameter near to where the head adjoins a stem of the geometric head design to provide reinforcement. In some embodiments, pores within the head contract in diameter from 1 mm at the tip of the head to 0.5 mm where the head adjoins a stem of the geometric head design to provide reinforcement.

[0013] In some embodiments, an article comprises a nasopharyngeal swab, and the article comprising a twist lock adjoining a head to a stem. [0014] In some embodiments, the head and the stem are made from the same material. In some embodiments, the head and the stem are made from different materials. In some embodiments, the head is 3D printed and the stem is made from conventional molding or subtractive manufacturing processes. In some embodiments, the head is a 3D printed elastomer and the stem is made from an injection molded plastic.

[0015] In some embodiments, an article comprises a nasopharyngeal swab, and the article comprises a fracture point that enables a head to be separated from a stem through mechanical action without use of a cutting tool.

[0016] In some embodiments, the head may be separated from the stem through a twisting motion. In some embodiments, the head may be separated from the stem through a bending motion.

[0017] In some embodiments, the fracture point is a multi-strand helix. In some embodiments, the fracture point is a multi-strand helix with an inner cylindrical core.

[0018] In some embodiments, the fracture point is a wedge removed from the article.

[0019] In some embodiments, an article comprises a nasopharyngeal swab, and the article comprises a coiled support structure that allows for quick detachment of the nasopharyngeal swab and minimal residue to be left on a surface of the nasopharyngeal swab.

[0020] In some embodiments, an article comprises a nasopharyngeal swab, and the article comprises a support structure configured to fracture below an outer plane of the nasopharyngeal swab such that a majority of residual support protrusions are below the outer plane. [0021] In some embodiments, a cavity is formed from a parabolic shape. In some embodiments, the cavity is greater than 0.1 mm and less than 1 mm deep.

[0022] In some embodiments, the support structure necks down to a point greater than 0.05 mm and less than 0.5 mm. In some embodiments, the support structure necks down to its narrowest point below the outer plane of the nasopharyngeal swab.

[0023] In some embodiments, an article comprises a nasopharyngeal swab, and the article comprises a support structure configured to be removed in a single lateral motion without use of additional cutting devices.

[0024] In some embodiments, the nasopharyngeal swab is supported by 4-6 support pillars. In some embodiments, each pillar contains between 20-30 contact points. In some embodiments, each contact point contains 1-4 pins. In some embodiments, the nasopharyngeal swab is supported by 80-720 pins. In some embodiments, the nasopharyngeal swab is supported by pins that are conical in shape, tapering down to 0.2-0.4 mm at an intersection within the nasopharyngeal swab.

[0025] In some embodiments, a nasopharyngeal swab is made from an elastomeric material. In some embodiments, a nasopharyngeal swab is made from a photo-cured elastomeric material. In some embodiments, a nasopharyngeal swab is made from a 3D printed elastomeric material. In some embodiments, a nasopharyngeal swab is made from a 3D printed, photo-cured, elastomeric material. In some embodiments, a nasopharyngeal swab is made from a 3D printed, photocured, phase-separated elastomeric material. In some embodiments, a nasopharyngeal swab is made from a 3D printed, photo-cured, polymerization- induced-phase-separated (PIPS) elastomeric material. In some embodiments, a nasopharyngeal swab is made from a 3D printed, one-part, photo-cured, polymerization-induced-phase-separated (PIPS) elastomeric material.

[0026] In some embodiments, a nasopharyngeal swab is made from 3D printable rubber with a strain capacity >150% and a tear strength > 25 MJ/m³.

[0027] In some embodiments, a nasopharyngeal swab is made from 3D printable rubber with a hardness >Shore A 75 and a strain capacity >150%.

[0028] In some embodiments, a nasopharyngeal swab is made from 3D printable rubber with a hardness >Shore A 88 and a strain capacity >200%.

BRIEF DESCRIPTION OF DRAWINGS

[0029] Fig. 1 depicts a portion of an exemplary nasopharyngeal swab having markings thereon.

[0030] Fig. 2A depicts a portion of an exemplary nasopharyngeal swab having a 90° engraving angle.

[0031 ] Fig. 2B depicts a portion of an exemplary nasopharyngeal swab having a >90° engraving angle.

[0032] Fig. 3A depicts a head portion of an exemplary nasopharyngeal swab having a Voronoi surface lattice.

[0033] Fig. 3B depicts a portion of a head portion of an exemplary nasopharyngeal swab having a Voronoi surface lattice.

[0034] Fig. 4 depicts a portion of an exemplary nasopharyngeal swab having a helical or rope-like braid of material as a break-point.

[0035] Fig. 5 depicts an exemplary wedge-like break-point in a swab stem.

[0036] Fig. 6 depicts a portion of an exemplary coiled support structure for a nasopharyngeal swab. [0037] Fig. 7 depicts a portion of an exemplary zipper support embedded into cavity contact-points on a nasopharyngeal swab.

[0038] Fig. 8 depicts a portion of an exemplary zipper support embedded into cavity contact-points on a swab with a wedge-like break-point and swab-head.

[0039] Fig. 9A depicts a bottom view of an exemplary stack of 16 swabs and 9 zipper supports with each zipper support connecting 4 adjacent swabs.

[0040] Fig. 9B depicts a close-up side view of an exemplary stack with 1 zipper support in the middle connecting two swabs on either side through branches.

[0041 ] Fig. 9C depicts an exemplary stack of 32 swabs with Voronoi swab heads and numbered markings.

[0042] Fig. 10 depicts an exemplary helical zipper-mechanism.

DETAILED DESCRIPTION

[0043] The present disclosure provides several embodiments for, e.g., the design of a nasopharyngeal swab as well as the design of a support structure for a swab. In some embodiments, a single swab is used to test several infections.

[0044] In some embodiments, the swab comprises a 3D printed elastomeric material. In some embodiments, the elastomeric material is able to be processed and patterned via additive manufacturing and has the requisite mechanical properties to enable use as a swab. In some embodiments, this is achieved through the use of a phase-separated 3D printable material such as the Adaptive Elastic ToughRubber (ETR) 90 resin.

[0045] In some embodiments, there are several specific design innovations which are added to the swab. For example, a set of markings on the shaft enables a health care provider to understand how deeply the swab has been inserted into a subject. Additionally, for example, an interlocking twist-lock mechanism enables the conjoining of two potentially different parts to be connected together and used as a single swab. As another example, a fracture point may enable the elastomeric material to be broken and the sample collecting head removed.

[0046] In some embodiments, a support comprises a coil support structure such that the swab can easily be removed from a printing scaffold. In some embodiments, a support is below the surface of the swab or the junction point that is below the surface of the swab. In some embodiments, a zipper removal function for the support structure next to the swab allows for a single (e.g. linear) movement and removal of supports rapidly and effectively with minimal post-process time.

Markings

[0047] In some embodiments, a swab comprises markings. For example, in some embodiments the swab comprises markings on the swab shaft. In some embodiments, the markings are numbers.

[0048] When a healthcare provider is collecting a sample, a swab is inserted into the patient's nasal (or NP) cavity. In traditional swabs, the health care provider does not know how far the swab has been inserted; however, normal swab insertion depth is typically somewhere between 75 and 100 mm into an average adult patient. In some embodiments, the ability to know how far the swab has been inserted helps the health care provider know if they need to apply extra pressure to the swab to enable it to pass further into the patient or if they need to be gentler with the swab. In some embodiments, this improves the ability to sample from a diverse patient population, including pediatric patients. As such, in some embodiments, markings are placed along the length of the shaft with numbers, letters or symbols. Fig. 1 depicts a portion of an exemplary swab having markings (3) on the shaft (7). In some embodiments, the markings enable the health care provider to understand how far the swab has been inserted into the subject. For example, in some embodiments, a swab of 150 mm in total length has a breaking point at 50 mm and has markings starting at 70 mm from the tip of the head. In some embodiments, the marking starting at 70 mm from the tip of the head are denoted by a “7” on the swab. In some embodiments, the markings continue until 140 mm from the tip of the head. In some embodiments, a marking of “14” is provided at 140 mm. In some embodiments, markings appear at 10 mm intervals.

[0049] In some embodiments, markings are engraved directly through the 3D printing process. In some embodiments, the markings are effectively cleaned to enable the outer surface of the swab to be smooth for gentle insertion into a patient. In some embodiments, the swab does not have raised bumps. In some embodiments, the markings are sunk down below the outer surface hull. In some embodiments, the markings do not form right angles (90°) in their engraving. For example, in some embodiments, markings have gentle slopes. Fig. 2A depicts a portion of an exemplary nasopharyngeal swab having a 90° engraving angle (201 ) which may trap, for example, resin (202). Fig. 2B depicts a portion of an exemplary nasopharyngeal swab having a >90° engraving angle. In some embodiments, decreasing the number of hard edges on the swab also decreases the number of potential pain points. For example, in some embodiments, gentler slopes facilitate easier cleaning and decrease the potential for uncured resin and any toxicity issues which may result from trapped and uncured resin. In some embodiments, angles of > 90 and < 180 (with respect to the outer plane of the swab) are used to ensure proper cleaning and decrease sharp edges. Swab head

[0050] In some embodiments, the end or ‘head’ of the swab is used to collect a mucus sample from the nasopharyngeal cavity. In some embodiments, the swab head is soft and flexible enough to collect mucus without discomfort to the patient. In some embodiments, the swab head mimics or surpasses the comfort of fibrous heads seen on standard nasopharyngeal swabs. In some embodiments, a swab head is in the form of a porous dome or a Voronoi surface lattice with 90 - 150 random seed points and 0.4 - 0.5 mm thick walls/struts. In some embodiments, the pores gradually increase in size from about 0.5 mm at the base to about 1 - 1.5 mm at the top. In some embodiments, pores allow mucus to seep into a hollow center of the head, for example, as the health care provider rotates the swab. Fig. 3 depicts a head portion of an exemplary nasopharyngeal swab having a Voronoi surface lattice. In some embodiments, the pores are smaller and denser at the bottom of the head to ensure a strong interface with the rest of the swab body. In some embodiments, thin walls of the head allow it to collapse and deform at an angle of up to about 120 degrees from its axis with minimal force so the health care provider can orient the swab after insertion to collect a better mucus sample. In some embodiments, the collapsible nature of the swab also minimizes discomfort to the patient in case the health care provider pushes the swab further after it touches the end of the nasopharyngeal cavity.

Twist-lock

[0051] In some embodiments, a swab comprises a twist lock. In some embodiments, a twist lock allows parts of the same material or of two different materials. In some embodiments, one part is manufactured by additive manufacturing and another manufactured by conventional manufacturing. In some embodiments, a twist lock joining one part is manufactured by additive manufacturing and another manufactured by conventional manufacturing. In some embodiments, parts are formed together and hold a global shape facilitating use as a swab and collection of a sample. In some embodiments, the twist lock is configured to quickly detach (unscrewed, unlatched) two parts from each other. For example, once used to collect the sample, the swab may be separated and the head with the sample collected with the remaining portion (stem) discarded. In some embodiments, a 3D printed swab head is a soft flexible material and a rigid stem is injection molded. In some embodiments, the head and stem are of compatible geometries such that they may be interlocked together after manufacturing, sterilized, utilized to collect sample, and finally detached. In some embodiments, head and stem components may be 3D printed. In some embodiments, a 3D printed head and stem are of a soft material, or one being a soft material and the other a rigid plastic. In some embodiments, the head is an elastomeric material with a durometer (hardness) of < 100 Shore A. In some embodiments, the stem is a material of compatible modulus to the head or a rigid plastic.

Fracture point

[0052] In some embodiments, a single component swab may be broken into two pieces and the head saved for sample collection. In some embodiments, a swab comprises a fracture point that facilitates breaking the swab into at least two pieces. In some embodiments, a swab comprises a fracture point that facilitates breaking the swab into two pieces. In some embodiments, a swab comprises a fracture point that facilitates breaking the swab into at least two pieces with one piece comprising the head. In some embodiments, a swab comprises a fracture point that facilitates breaking the swab into two pieces with one piece comprising the head. In some embodiments, a swab comprises a fracture point that facilitates breaking the swab into at least two pieces with one piece comprising the head, and the head is saved for sample collection.

[0053] In some embodiments, the fracture point is configured to locally generate significant stress in an elastomeric part such that the local strains generated exceed the strain capacity of the elastomer generating high local deformations, inducing cracking in the elastomer and then shearing of the elastomer. In some embodiments, a fracture point comprises a helix and/or a braid. Fig. 4 depicts a portion of an exemplary nasopharyngeal swab having a helical or rope-like braid of material as a break-point. In some embodiments, a swab comprises a wedge-like fracture point. In some embodiments, the fracture point is in the stem. Fig. 5 depicts an exemplary wedge-like break-point in a swab stem. In some embodiments, a swab has necking with notching on both sides.

[0054] In some embodiments, the braid is similar to that of a rope. In some embodiments, when the braid is rotated in one direction, the braid compresses upon itself, reinforcing itself, and allowing for mechanical integrity of the swab; however, when the braid is rotated counter to its preferred axis, the strands of the braid open, causing high local deformations and fracturing of the elastomer. In some embodiments, a health care provider inserts the swab with a counter-clockwise (or clockwise) motion rotating the swab in their fingers as it is inserted, as sample is collected, and as it is withdrawn; and, once the sample is withdrawn, grasping the stem and the head in separate hands, rotating in a clockwise (or counter-clockwise) motion to generate local stresses which enable elastomeric part to fracture and the head to be collected. In some embodiments, the swab is fractured when the swab head was already in the sample collection vial to minimize any spread or scatter during the swab head removal.

[0055] In some embodiments, the swab comprises one or more notches on the sides of the part. In some embodiments, the notch is at 45 degree angles, with one notch on each side coming in —1/3 the width of the swab. In some embodiments, the swab comprises a wedge version that has a clear pass-through. Fig. 5 depicts an exemplary wedge-like break-point in a swab stem. In some embodiments, the notch in the swab is designed to generate weakness along one axis of deformation I bending. In some embodiments, bending along the perpendicular axis or rotational torsion remains highly resisted, however bending along the weak-axis, in repeated motions, positively and negatively generates cracks in the leading edges of the cavity enabling the swab to tear along that line (e.g., the head and the shaft being grasped in separate hands).

Supports

[0056] In some embodiments, a swab is 3D printed connected to a support. In some embodiments, supports facilitate removing a swab from supports and the removed swab has minimal protrusions or bumps. In some embodiments, bumps and/or protrusions are undesirable and, if remaining on the surface of the swab, may cause significant discomfort to the patient during testing. In some embodiments, supports as disclosed herein improve patient outcomes and facilitate automation in the printing and post processing of swabs.

[0057] In some embodiments, a support is a coiled support. In some embodiments, the coiled support structure allows for a weaker interaction between the swab and the support allowing detachment in the green state before post processing which enables minimal residue to be left on the surface of the swab. Fig. 6 depicts a portion of an exemplary coiled support structure for a nasopharyngeal swab. In some embodiments, a hexagonal lattice type array has a separation of 2.86 mm which is the diameter of the swab. In some embodiments, a helix shape of the swab’s body allows the connection between the horizontal supports with a clear space of 140 microns to avoid unwanted contact points between the supports and the swab. In some embodiments, based on this clearance and the angle of the helix, 912 microns is the width of the supports. In some embodiments, the supports are distributed along the body of the swab up to the head of the swab, around 130 mm. In some embodiments, a set of 3 supports is positioned every 10 mm rotating 60 degrees to follow the helix shape. In some embodiments, every support connects each swab with another. In some embodiments, based on the center of mass of every support, the minimum to make them printable is 45 degrees, and, in some embodiments, to keep the separation of 2.86 mm and the height of 10mm, the support is placed using 57 degrees from the horizontal plane. In some embodiments, the contact point of the supports with the swab stem is 210 microns (3 pixels), and the contact point of the horizontal support is 912 microns. Almost 1 mm is needed to break the swab in the contact point of the horizontal support and the stem of the swab.

[0058] In some embodiments, a support is a cavity support. In some embodiments, rather than having the contact point of the support (i.e. where the support beam intersects the swab) on the surface of the swab, there is a cavity which is made in the surface of the swab and the contact point of the support is within the cavity; e.g., located beneath the surface of the swab. In some embodiments, when the support structures are tom from the swab, any torn edges of the support beams are under the surface of the swab (within the cavity), and, thence, the surface of the swab is protrusion-free. In some embodiments, removal of supports is facilitated without protruding nubs on the surface of the swab which could cause irritation to the patient during sample collection.

[0059] In some embodiments, a support has a zipper structure. In some embodiments, the contact point of each support beam is small enough such that the focus of a tear (formed by pulling the swab away from the support structure) is highly local to the contact point (as opposed to occurring randomly along the beam, as may occur should the beam be sufficiently thick as to not preferentially direct the force of the tearing motion). In some embodiments with a plurality of small support points along the length of the swab, a single smooth motion can cleanly break each support beam at a precise location. In some embodiments with a high vertical density of these small supports, as each successive support beam experiences the tearing force, it will be exerted along a sharper angle, relative to the support beam, thereby increasing the torsion on that contact, making it easier to tear. In some embodiments, these designs create a “zipper”-like effect, whereby a smooth tearing motion easily and cleanly removes swabs from such a support stack. Fig. 7 depicts a portion of an exemplary zipper support embedded into cavity contact-points on a nasopharyngeal swab. Fig. 8 depicts a portion of an exemplary zipper support embedded into cavity contact-points on a swab with a wedge-like break-point and swab-head.

[0060] In some embodiments, this zipper removal enables deconstruction of a brick of printed swabs from their support structure with minimal effort. In some embodiments, each support has periodic protrusions or ‘branches’ that contact the swabs in a circular region. In some embodiments, these branches have a diameter of 1 .1 - 2 mm at the support and 0.3 - 0.5 mm at the contact point on the swab. In some embodiments, a 0.4 - 1 mm fillet blends the protrusions into the support surface to ensure that any stresses are concentrated only at the interface between the protrusion and the surface of the swab. In some embodiments, this feature also ensures that no residual bumps are left on the surface of the swab after removal of the supports. In some embodiments, the supports are arranged in a grid so that each support stem connects up to 4 swabs. Fig. 9A depicts a bottom view of an exemplary stack of 16 swabs and 9 zipper supports with each zipper support connecting 4 adjacent swabs. Fig. 9B depicts a close-up side view of an exemplary stack with 1 zipper support in the middle connecting two swabs on either side through branches. Fig. 9C depicts an exemplary stack of 32 swabs with Voronoi swab heads and numbered markings. In some embodiments, the minimum distance between the support stem and the swab can range from 0.4 - 1.5 mm.

[0061] In some embodiments, the zipper-mechanism is combined with the helix shape of the swab and the hexagonal lattice type array with a primitive unit cell of 4 swabs (4) and 5 thinner vertical supports (5) of 2 mm of diameter with an equidistant separation between the swabs of 5.72 mm of 60 degrees to complete the hexagonal shape in the lattice. The horizontal supports are in contact with the vertical stem and the swab with width point contact of 0.912 mm and 0.21mm, respectively, with a thickness of 0.21 mm for a total area of contact of 0.19152 mm² in the stem point of contact, 0.0441 mm² in the swab point of contact. In some embodiments, with more than 4 times greater point of contact in the stem, the zipper support is prepared to break in the contact point of the swab, allowing the separation of the array in a single-action movement. In some embodiments, the unit cell could be used to create a matrix with a length and width depending on the work area available in the 3D Printer. Fig. 10 depicts an exemplary embodiment having a helical zipper-mechanism.

Printing Process

[0062] In some embodiments, the swabs are printed upright as a stack of connected individual swabs with coil, cavity or zipper supports in a digital light processing DLP 3D printer with a 385 nm or 405 nm UV LED or Lamp. In some embodiments, 500 swabs can fit into a build area of 134.4 mm x 75.6 mm, or 8000 swabs can fit into a build area of 400 mm x 338 mm. In some embodiments, with an exposure duration of 17 - 21 seconds, a layer time of 40 - 50 seconds, and a layer height of 0.125 mm, the stack takes an average of 15 hours to print. In some embodiments, once completed, the residual resin is washed off the swabs in 99% pure isopropyl alcohol for 5 - 6 minutes. In some embodiments, the swabs are dried in an oven at 60°C with an exhaust of 0.33 air exchanges per minute, or greater, for 1 hour, followed by a final cure in an LC-3D print box for 20 minutes. In some embodiments, removal of the swabs from their support structures can occur at any point along the post-processing route (from removal from the 3D printers to final cure with UV light). In some embodiments, if removed before the final cure step (while in the green state) a scaffold is utilized which holds the swabs in a linear fashion for drying and UV curing. In some embodiments, the scaffold may or may not be employed for the washing step. In some embodiments, the wash step may, by mechanical agitation and minimal solvent swelling, detach the swabs from their support structures, after which the swabs are collected. In some embodiments, after the swabs are collected, they are placed into scaffolds to dry and post cure.

Claims

What is claimed is:

1) An article comprising a nasopharyngeal swab, the article comprising an engraving that denotes a depth of insertion of the nasopharyngeal swab.

2) The article of claim 1 , wherein the engraving is a number.

3) The article of claim 1 , wherein the engraving is a letter.

4) The article of claim 1 , wherein the engraving is a symbol.

5) The article of claim 1 , wherein the engraving is a combination of one or more letters, numbers and/or symbols.

6) The article of claim 1 , wherein the edges of the engraving range from > 90 degrees and < 180 degrees.

7) The article of claim 1 , wherein the edges of the engraving range from > 90 degrees and < 150 degrees.

8) The article of claim 1 , wherein the edges of the engraving range from > 90 degrees and < 135 degrees.

9) The article of claim 1 , wherein the edges of the engraving range from > 90 degrees and < 120 degrees.

10) An article comprising a nasopharyngeal swab, the article comprising a geometric head design wherein a head of the geometric head design is hollow.

11 ) The article of claim 10, wherein individual strut thicknesses of the geometric head design range from 0.1 to 1 mm.

12) The article of claim 10, wherein individual strut thicknesses of the geometric head design range from 0.2 to 0.8 mm.

13) The article of claim 10, wherein individual strut thicknesses of the geometric head design range from 0.4 to 0.6 mm. ) The article of claim 10, wherein individual strut thicknesses of the geometric head design range from 0.45 to 0.55 mm. ) The article of claim 10, wherein pores within the head range in diameter.) The article of claim 10, wherein pores within the head contract in diameter near to where the head adjoins a stem of the geometric head design to provide reinforcement. ) The article of claim 10, wherein pores within the head contract in diameter from 1 mm at the tip of the head to 0.5 mm where the head adjoins a stem of the geometric head design to provide reinforcement. ) An article comprising a nasopharyngeal swab, the article comprising a twist lock adjoining a head to a stem. ) The article of claim 18, wherein the head and the stem are made from the same material. ) The article of claim 18, wherein the head and the stem are made from different materials. ) The article of claim 18, wherein the head is 3D printed and the stem is made from conventional molding or subtractive manufacturing processes. ) The article of claim 18, wherein the head is a 3D printed elastomer and the stem is made from an injection molded plastic. ) An article comprising a nasopharyngeal swab, the article comprising a fracture point that enables a head to be separated from a stem through mechanical action without use of a cutting tool. ) The article of claim 23, wherein the head may be separated from the stem through a twisting motion. ) The article of claim 23, wherein the fracture point is a multi-strand helix. ) The article of claim 23, wherein the fracture point is a multi-strand helix with an inner cylindrical core. ) The article of claim 23, wherein the head may be separated from the stem through a bending motion. ) The article of claim 23, wherein the fracture point is a wedge removed from the article. ) An article comprising a nasopharyngeal swab, the article comprising a coiled support structure that allows for quick detachment of the nasopharyngeal swab and minimal residue to be left on a surface of the nasopharyngeal swab.) An article comprising a nasopharyngeal swab, the article comprising a support structure configured to fracture below an outer plane of the nasopharyngeal swab such that a majority of residual support protrusions are below the outer plane. ) The article of claim 30, wherein a cavity is formed from a parabolic shape.) The article of claim 30, wherein the cavity is greater than 0.1 mm and less than 1 mm deep. ) The article of claim 30, wherein the support structure necks down to a point greater than 0.05 mm and less than 0.5 mm. ) The article of claim 30, wherein the support structure necks down to its narrowest point below the outer plane of the nasopharyngeal swab. ) An article comprising a nasopharyngeal swab, the article comprising a support structure configured to be removed in a single lateral motion without use of additional cutting devices. ) The article of claim 35, wherein the nasopharyngeal swab is supported by 4-6 support pillars. ) The article of claim 36, wherein each pillar contains between 20-30 contact points. ) The article of claim 37, wherein each contact point contains 1-4 pins. ) The article of claim 35, wherein the nasopharyngeal swab is supported by 80- 720 pins. ) The article of claim 35, wherein the nasopharyngeal swab is supported by pins that are conical in shape, tapering down to 0.2-0.4 mm at an intersection within the nasopharyngeal swab. ) A nasopharyngeal swab made from an elastomeric material. ) A nasopharyngeal swab made from a photo-cured elastomeric material. ) A nasopharyngeal swab made from a 3D printed elastomeric material. ) A nasopharyngeal swab made from a 3D printed, photo-cured, elastomeric material. ) A nasopharyngeal swab made from a 3D printed, photo-cured, phase- separated elastomeric material. ) A nasopharyngeal swab made from a 3D printed, photo-cured, polymerization-induced-phase-separated (PIPS) elastomeric material. ) A nasopharyngeal swab made from a 3D printed, one-part, photo-cured, polymerization-induced-phase-separated (PIPS) elastomeric material. ) A nasopharyngeal swab made from 3D printable rubber with a strain capacity >150% and a tear strength > 25 MJ/m3. ) A nasopharyngeal swab made from 3D printable rubber with a hardness >Shore A 75 and a strain capacity >150%. ) A nasopharyngeal swab made from 3D printable rubber with a hardness >Shore A 88 and a strain capacity >200%.

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